Source code for colour.models.rgb.common

# -*- coding: utf-8 -*-
"""
Common RGB Colour Models Utilities
==================================

Defines various RGB colour models common utilities.

See Also
--------
`RGB Colourspaces Jupyter Notebook
<http://nbviewer.jupyter.org/github/colour-science/colour-notebooks/\
blob/master/notebooks/models/rgb.ipynb>`_
"""

from __future__ import division, unicode_literals

from colour.colorimetry import ILLUMINANTS
from colour.models.rgb import RGB_COLOURSPACES, RGB_to_XYZ, XYZ_to_RGB

__author__ = 'Colour Developers'
__copyright__ = 'Copyright (C) 2013-2019 - Colour Developers'
__license__ = 'New BSD License - https://opensource.org/licenses/BSD-3-Clause'
__maintainer__ = 'Colour Developers'
__email__ = 'colour-science@googlegroups.com'
__status__ = 'Production'

__all__ = ['XYZ_to_sRGB', 'sRGB_to_XYZ']


[docs]def XYZ_to_sRGB( XYZ, illuminant=ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['D65'], chromatic_adaptation_transform='CAT02', apply_encoding_cctf=True): """ Converts from *CIE XYZ* tristimulus values to *sRGB* colourspace. Parameters ---------- XYZ : array_like *CIE XYZ* tristimulus values. illuminant : array_like, optional Source illuminant chromaticity coordinates. chromatic_adaptation_transform : unicode, optional **{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp', 'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco', 'Bianco PC'}**, *Chromatic adaptation* transform. apply_encoding_cctf : bool, optional Apply *sRGB* encoding colour component transfer function / opto-electronic transfer function. Returns ------- ndarray *sRGB* colour array. Notes ----- +------------+-----------------------+---------------+ | **Domain** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``XYZ`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ +------------+-----------------------+---------------+ | **Range** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``RGB`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ Examples -------- >>> import numpy as np >>> XYZ = np.array([0.20654008, 0.12197225, 0.05136952]) >>> XYZ_to_sRGB(XYZ) # doctest: +ELLIPSIS array([ 0.7057393..., 0.1924826..., 0.2235416...]) """ sRGB = RGB_COLOURSPACES['sRGB'] return XYZ_to_RGB( XYZ, illuminant, sRGB.whitepoint, sRGB.XYZ_to_RGB_matrix, chromatic_adaptation_transform, sRGB.encoding_cctf if apply_encoding_cctf else None, )
[docs]def sRGB_to_XYZ( RGB, illuminant=ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['D65'], chromatic_adaptation_method='CAT02', apply_decoding_cctf=True): """ Converts from *sRGB* colourspace to *CIE XYZ* tristimulus values. Parameters ---------- RGB : array_like *sRGB* colourspace array. illuminant : array_like, optional Source illuminant chromaticity coordinates. chromatic_adaptation_method : unicode, optional **{'CAT02', 'XYZ Scaling', 'Von Kries', 'Bradford', 'Sharp', 'Fairchild', 'CMCCAT97', 'CMCCAT2000', 'CAT02_BRILL_CAT', 'Bianco', 'Bianco PC'}**, *Chromatic adaptation* method. apply_decoding_cctf : bool, optional Apply *sRGB* decoding colour component transfer function / electro-optical transfer function. Returns ------- ndarray *CIE XYZ* tristimulus values. Notes ----- +------------+-----------------------+---------------+ | **Domain** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``RGB`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ +------------+-----------------------+---------------+ | **Range** | **Scale - Reference** | **Scale - 1** | +============+=======================+===============+ | ``XYZ`` | [0, 1] | [0, 1] | +------------+-----------------------+---------------+ Examples -------- >>> import numpy as np >>> RGB = np.array([0.70573936, 0.19248266, 0.22354169]) >>> sRGB_to_XYZ(RGB) # doctest: +ELLIPSIS array([ 0.2065429..., 0.1219794..., 0.0513714...]) """ sRGB = RGB_COLOURSPACES['sRGB'] return RGB_to_XYZ( RGB, sRGB.whitepoint, illuminant, sRGB.RGB_to_XYZ_matrix, chromatic_adaptation_method, sRGB.decoding_cctf if apply_decoding_cctf else None, )